CCAPrint Newsletter for Model 204 and System 1032 Users

Many organizations have reached or are approaching the requirement for 24x7 operations (twenty-four hours per day, seven days per week). Others support extremely large user environments or process millions of transactions per day; some do both. In all these instances, the size of CCAJRNL can become a significant factor limiting the "uptime" of the run. If this critical Model 204 recovery dataset fills up, the run terminates abnormally, necessitating what might be a lengthy recovery process.

Ring streams and perpetual journaling, available under the three operating systems (MVS, VM, and VSE) provide a way to avoid this potentially serious service disruption and costly downtime for mission critical and other production systems.

CCAJRNL can be defined as a collection of multiple datasets, a ring stream, each of which still has finite capacity. However, when one dataset in this collection reaches its capacity (that is, fills and triggers a B37, D37, or E37 ABEND), the following actions are taken:

This facility eliminates the need to dedicate massive amounts of DASD for CCAJRNL and removes the uncertainty inherent in the space allocation for this dataset. A reasonable ring-stream configuration might consist of:

//CTL DD DSN=JRNL.CTL,SPACE=(TRK,(1,1)),... //JRNL1 DD DSN=CCAJRNL1,SPACE=(CYL,500),... //JRNL2 DD DSN=CCAJRNL2,SPACE=(CYL,500),... //JRNL3 DD DSN=CCAJRNL3,SPACE=(CYL,500),... //CCAIN DD * DEFINE STREAM CCAJRNL WITH SCOPE=SYSTEM RING=(JRNL1,JRNL2,JRNL3) - OFFLOAD=OFFTAPE AUTOOFFLOAD=2 CONTROL=CTL CLOSE=NOAUTO DEFINE STREAM OFFTAPE WITH SCOPE=SYSTEM CONCATENATE=(OFFT1,OFFT2,OFFT3) DEFINE DATASET OFFT1 WITH SCOPE=SYSTEM DSN=JRNLOFF1 LABEL=SL POSITION=1 - VOLUME=TAP001 UNIT=CART DEFINE DATASET OFFT2 LIKE OFFT1 WITH SCOPE=SYSTEM DSN=JRNLOFF2 VOLUME=TAP002 DEFINE DATASET OFFT3 LIKE OFFT1 WITH SCOPE=SYSTEM DSN=JRNLOFF3 VOLUME=TAP003
(Dynamic tape support under VM and VSE is either not available or is limited in such a way as to require dedicated tape drives for tape offloads in those environments.)
CCAJRNL and the BSAM-writes directed to it now behave as follows:

JRNL1 becomes the active dataset for CCAJRNL.

When JRNL1 fills, it is closed and scheduled for automatic, asynchronous offloading.

JRNL2 is opened and becomes the active dataset for CCAJRNL.

When JRNL2 fills, it is closed and an asynchronous OFFLOAD pseudo-subtask is started because AUTOOFFLOAD=2.

JRNL3 becomes the active dataset for
CCAJRNL.

A mount request is now dynamically issued for OFFT1, VOL=SER=TAP001.

JRNL1 and JRNL2 are offloaded asynchronously to OFFT1.

When JRNL3 fills, it is closed and scheduled for asynchronous offloading.

Assuming the previous offload has completed, JRNL1 is opened and becomes the active dataset for CCAJRNL. The previous contents of JRNL1 are overwritten.

When JRNL1 fills, another asynchronous offload is initiated to OFFT2, because another two ring members have filled and AUTOOFFLOAD=2.

This process continues until the offload stream and all ring members are full and no further offloads can be performed. In this example, CCAJRNL would reach a full condition when:

In the next several installments on this topic, I will discuss in more detail some of the nuances of ring-stream processing including:

Optimizing space allocation for ring members

Messages associated with ring-stream operations

Warning track feature for monitoring ring-stream capacity and approaching full conditions

Using CCAJRNL ring streams as CCARF in subsequent recovery runs

Archiving ring streams for future use by AUDIT204 or by the media recovery facility (the REGENERATE command)

Computer Corporation of America has just returned from the 1998 Very Large Database (VLDB) Summit conference in Beverly Hills, California. CCA was a Platinum Sponsor for this event, with a speaking spot in the opening plenary session and a prime position in the vendor display area. Delegates witnessed live demonstrations of data mining with Model 204 over the Web and the latest client/server architecture of MarketPulse.

Unfortunately, only two CCA customers submitted VLDB surveys this year, which makes it all the more impressive that Roadway Express once again took Grand Prize honors. The survey included a new measure this year: "OLTP: Most Transactions Per Second - all environments." Since the measure was new, Roadway did not have historical data they could use and had to take the measure during a quiet period. Notwithstanding, they weighed in with an astonishing 1,820 tps. Next year, we can expect this figure to double.

A little bird tells us that, although the other Model 204 entrant did not win a Grand Prize, they will figure in the top 10 in 3 distinct categories when the full results are announced. In the meantime, congratulations once more to Roadway. May they keep on truckin'.

If you have had difficulty dialing in to On-Que, which provides customer access to the Model 204 problem tracking system, please make a note of the area code change for future reference. The phone number for On-Que is now: 978-557-0122.

CCA is delivering to beta sites today the software to enable customers to take advantage of new features and functionality provided in V2.1 of the System 1032 ODBC Driver.

The System 1032 ODBC V2.1 Driver is a layered product that allows client applications to access a System 1032 database running on an OpenVMS system via a TCP/IP network connection.

Version 2.1 provides new functionality, performance, and usability enhancements. Of particular note are:

Full compliance with ODBC Version 2 Core and Level 1 functions and all Level 2 functions (except scrollable cursor support). This includes SIMBA ODBC Conformance Level 2.5.

16-bit, 32-bit, and Java Client ODBC Drivers for the Windows 3.11, Windows 95, and Windows NT client applications.

Performance enhancements over ODBC V1.0, and 28% performance increase over T2.0 when using Alpha/VMS 7.1 with I/O enhancement.

The following diagram shows the components required to utilize the new functionality.

Join us at IMPACT'98, the leading international forum for users of Computer Corporation of America products Model 204, System 1032, and MarketPulse. IMPACT'98 welcomes managers, developers, DBAs, analysts, end-users, vendors, and customers - anyone with an interest in the products of Computer Corporation of America.

IMPACT'98 will provide tremendous learning opportunities. The Internet, the enterprise-wide server, and the Year 2000 challenge will be featured, along with all the latest developments, release enhancements, and application techniques. See the latest tools. Talk to software engineers. Learn from the experts. This is an excellent opportunity for education and training on the approaches and tools to satisfy the demands of information-hungry users!

For details, call the IMPACT office at (781) 595-2005, send e-mail to admin@impactug.org, or access the IMPACT home page via: http://www.impactug.org.

Learn how Model 204 and the Internet can increase your options to meet critical business needs as new technologies, legacy systems, tight budgets, and intensified user demands stretch IT departments beyond available resources.

Hear about ways to enhance the benefits you receive from CCA products through performance and tuning, and new product releases - including Web Access, MQ/204, MP/204, and Connect* - that address parallel processing, client/server computing, and Internet/Intranet/Web access.

Learn how System 1032 and the Internet can increase your options to meet critical business needs as new technologies, legacy systems, tight budgets, and intensified user demands stretch IT departments beyond available resources.

Hear about ways to enhance the benefits you receive from CCA products through performance and tuning, and new releases of products - including access to System 1032 via the new ODBC Driver - that address client/server computing and Internet - Intranet - Web access to System 1032.

Free Model 204 V4R1 Update Class Registration When You Register for IMPACT'98

Maximize your training dollars when you come to IMPACT'98. Register and attend IMPACT'98 and you can attend the June 4th Model 204 V4R1 Update Class for free! This special class, which begins the day after the conclusion of the IMPACT conference, will be held at the Hyatt Regency Miami Hotel. If you do not attend the conference, the cost is $350 per person.

You can register for the class on the IMPACT'98 registration form. Confirmation will be sent after receipt of conference registration. Space is limited and slots will be filled on a first-come-first-served basis. For IMPACT'98 registration and information, please contact the IMPACT office at (781) 595-2005, or send e-mail to admin@impactug.org.